<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Symbol</title>
</head>
<body>
    
</body>
<script>
    let user=Symbol("user");
    let user2=Symbol("uesr");
    console.log(user===user2);
    console.log(typeof user2);
    
    let user3=Symbol.for("user");
    let user4=Symbol.for("user");
    console.log(user3===user4);
    console.log(user3.description);
    console.log(Symbol.keyFor(user4));
</script>
</html>